The long range goal is to examine the development of the vertebrate central nervous system with sufficiently sensitive biochemical and cell biological techniques that conclusions can be drawn concerning the sequence of potential morphogenetic interactions of individual neurons. Our research is directed at the question of how neurons in the developing eye make the right connections within the brain. Essentially two major objectives have been proposed: 1) Mapping the initial development of retinal projections in Xenopus, and their modification during metamorphosis, with EM-autoradiographic (AR) techniques; and 2) evaluating retinal specification with an in vitro assay of selective cell adhesion.